I know how the lifter got *that bad*-my one bonehead fault! (valuable lesson below) But I don't know what caused it to start failing in the first place. The motor was built 20 years ago and it did spend a lot of time parked but it had been great since I started driving it regularly in the summer of 2020. Long bonehad story below:
My wife and I were out on a slow neighborhood cruise one afternoon and I heard what sounded like a tire going flat but I could tell it was engine speed related so I eased it back home. Listening carefully under the hood I pinpointed the sound to the passenger valve cover. I popped off the valve cover, found the #7 exhaust rocker quite loose and figured the valves just needed adjustment (too much time around little British cars, I'd say.) So BONEHEAD ME, I adjusted all of them, and *thought* something was strange about how much I had to adjust that particular rocker. (Hindsight, I should have known something was really wrong right then and there) But the engine fired up and sounded normal again. That night we took the L.A. freeways 20 miles to get ice cream, even cruised the Bob's Big Boy Friday night car gathering on the way home, all was great. In the morning we took it 15 miles uphill on the freeway to a cars and coffee and I thought I heard the sound coming back so after the meet we took the streets back . The sound definitely came back, slightly louder than it was the first time I heard it. As I was pretty much idleing it back down the hill, I gave it just a hint of gas to get around a cyclist and BAM that lifter must have really given up right there. It sounded like a big explosion with every revolution. I immediately shut off the motor and coasted to a stop. I pulled the valve cover, had my wife fire it up and could see that rocker not rocking. Pulled the pushrod and it was straight as an arrow so I knew it was cam lobe or lifter, Called AAA, towed her home and here we are today.
So, lesson for anyone reading this in the future, if your rocker arm is way out of adjustment and it's not because your rocker nut has backed off, stop right there, it's probably a bad lifter.
|